The Oyu Tolgoi copper and gold mine in southern Mongolia contains mineral resources that make it one of the worlds largest known copper and gold deposits. The project is a significant contributor to regional development and is jointly owned by Turquoise Hill Resources Ltd (66%) and the Government of Mongolia (34%). Turquoise Hill Resources is 50.8% owned by Rio Tinto Ltd. Oyu Tolgoi (OT) commenced open pit mining in 2011 and implemented an industry standard blast hole sampling, and ordinary kriging grade control block-out method. The OT surface mine geology team used to utilise four different mining and geology software packages (Vulcan, Minesight, Leapfrog and Digger) for grade control geology. Processing data through several software creates potential for errors and was not time-efficient. A year ago, the geology team started using Vulcan software for updating and grade block-out for the ore control block-out and implicit modelling software (Leapfrog) for the geological model update. This paper outlines how the grade control system was developed at OTs open pit mine, and how it is integrated into the mines reconciliation workflow and reporting systems. CITATION: Amar-Amgalan, S, Nomin-Erdene, J, Amarbold, T, Natsagdorj, K, Bayarmaa, B, Batbyamba, D, Sainzaya, T and Crook, G, 2019. Grade control improvements using Vulcan integrates and optimiser at the Oyu Tolgoi copper-gold mine, Mongolia, in Proceedings Mining Geology 2019, pp 466470 (The Australasian Institute of Mining and Metallurgy: Melbourne).